1. Field of the Invention
The present invention relates to golf club heads. More specifically, the invention relates to golf club heads that are top-head-weighted and aerodynamic shape. The invention describes various embodiments. The preferred embodiments describe a thicker and heavier top line region of club heads that taper along the vertical axis to a thinner bottom or sole line and also taper along the horizontal axis from a thinner heel to a thicker toe region.
2. Description of the Prior Art
By way of background, there are many variations of golf club designs, including drivers, irons and putters. The complexity of the engineering principles and material science involved in golf club designs are well known. The choice of materials and design for each component of a golf club (i.e., head, shaft, hosel, grip etc.) influence the performance of the club. Among the factors involved in golf club design are loft, lie and face angles, face size, sole curvature center of gravity, overall head weight and selection of materials.
Iron-type golf club heads can generally be divided into three groups: blades, muscle backs and cavity back designs. Blade designs are traditional type designs that are substantially uniform in appearance from the sole to the top line of the head. Some blade designs may have some tapering from a thinner top line to a wider sole. Muscle backs have a substantially traditional appearance very similar to blade designs, but have extra material on the back of the blade (i.e., in the form of a rib) that serve to lower the club head center of gravity. With the club head center of gravity lower than the ball center of gravity at contact, the launch angle of the resulting golf shot is increased. Cavity back head designs are contemporary designs that have a hollow space or cavity in the back of the club head opposite the striking face. Cavity back designs move some of the club mass to the perimeter of the club that allows the size of the club face to be increased resulting in a larger sweet spot.
The so-called “sweet spot” of a golf head is the area of the face of the club that results in a desirable golf show when striking a golf ball. The sweet spot of the club head is generally thought to be that area on the striking face of the club head immediately surrounding the center of gravity of the club head. Perimeter-weighted club heads (i.e., cavity back designs) are generally easier to hit than blades and muscle backs and are useful for less-skilled golfers Both blade and muscle back design have a smaller sweet spot than cavity backs. Blade and muscle back designs are typically used by skilled golfers. Golf head designs adding weigh members to the bottom or sole surface are known (i.e., U.S. Pat. Nos. 3,979,122 and 3,979,123).
A typical set of golf club irons includes eight or nine irons having variation in shaft length, weight, lie and loft among other variable characteristics. For example, the iron that is the lowest weight, longest shaft and the lowest loft is typically the number two iron. The iron having the shortest shaft and the highest loft is typically the wedge. The club head includes a face section for striking a golf ball. The angle between the face and a vertical plane is referred to as the loft angle. The lie angle is the angle formed by the club head and the club shaft.
The sole of the golf club is particularly important to the golf shot because it contacts and interacts directly with the ground during the golf shot. The larger the area of the sole, the more frictional resistance there will be with the ground when striking a golf ball.
It would be desirable to have a golf club that will more efficiently transfer the forces created during the golf swing to a golf ball so as to create a more controlled and/or longer distanced golf shot in comparison to contemporary golf club designs. In addition, it would be desirable to have golf clubs that have less ground resistance that easily go through turf and that have improved aerodynamics. The present invention is directed toward solving these needs.